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Boost dip at 4k

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Old 09-30-2004, 05:00 PM
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Default Boost dip at 4k
<center><img src="http://pictureposter.audiworld.com/64721/boost_9-30-04.jpg"></center><p>Anyone have ideas for this one? The boost dips consitently at about 4k, all the other logs I took tonight look much like this one (4th gear). I'm not sure what else to log.
Spec boost dives a little and picks back up a notch, but actual boost dives even lower. You can really feel the pause when you're driving.

Flex
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Old 09-30-2004, 05:24 PM
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Default limp mode?
any dtcs?
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Old 09-30-2004, 05:34 PM
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Nope, usually no DTC's. Once in a great while I will get overboost DTC.
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Old 09-30-2004, 05:42 PM
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odd, i can't think of any good reason why the ECU would request 0 boost. bad maf?
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Old 09-30-2004, 06:01 PM
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Looks like throttle cut. Log block 003 and see if your throttle is shutting there.
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Old 09-30-2004, 06:41 PM
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Agreed, 003 is needed. TC cause is a mystery though... High MAF or Knock readings?
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Old 09-30-2004, 06:58 PM
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Default Yep one of those could be it. A bad egt sensor could do it too. They
behave very funny. Could however just be a case of bad gas or very high ambient temps causing knock like you said. 003 would make it more clear.
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Old 09-30-2004, 07:01 PM
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Bingo!
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Old 09-30-2004, 07:02 PM
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It is only requesting 0 boost after he stopped going WOT....unless I'm missing something :/
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Old 09-30-2004, 09:53 PM
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Default ugh. braino
looking at the wrong thing again ;/

ignore me.

also vote maf, knock problems, possibly egt like funk says.
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